Synthetic Atf

Joined
Nov 1, 2011
Messages
236
Location
montana
I have a 1991 Dodge power ram 150 4x4 short bed truck with an A-518 non lock up transmission. I had the transmission re-built in September of 2012. Paid a lot of money for the re-build too. The transmission shop gave me a 2 year warranty on it which is expired now. When I asked about what fluid to run they said dexron3 and when I asked about a synthetic they said stay away from them the dexron3 will be just fine. So I have been running Napa house brand dexron3 in it and haven't had any issues it still shifts well when it's cold or hot. I'm going to be having some upgraded parts installed in this transmission, ether this spring with my tax return or this coming summer, I am going to have some 6 pinion steel planeterys installed up front in place of the aluminum 4 pinion planeterys and I am going to have a trans go shift kit installed. Transmission has to come out for these upgrades.m While its out I have decided I might as well run a better fluid then dexron3, it makes no sense to me to run such a dated fluid in a transmission that I will eventually have over 3 thousand dollars invested in.. I have been thinking about trying ether amsoil universal atf or mobil 1 synthetic universal or red line d4 atf or maybe even royal purple atf. I have also considered running the new dexron6 because I have heard it is a very good atf as well. People have also recommended valvoline maxlife to me. What synthetic fluid would work best forme? I live in idaho where winters are brutally cold and summers get pretty warm to, winter can get as cold as 30 below zero summer can get as hot as 100 degree. I have an external transmission cooler along with the factory tranny cooler.
 
Joined
Jan 24, 2014
Messages
34
Location
CA
I would check out some Dexron VI. Has lower viscosity numbers vs Maxlife which may be better for your low temps and some versions of Dexron VI are less expensive via Amazon. Check out Havoline or Mag1 Dexron VI on Amazon. You could also add some Lubegard Red or Platinum.
 
Joined
Nov 30, 2004
Messages
2,566
Location
SD
I second the ATF+4, though any of the syn universals you listed would be fine, too. I would not use the Dex VI, as this trans wasn't designed for low-visc fluid.
 
Joined
Jun 17, 2013
Messages
1,607
Location
USA, FLA
Originally Posted By: pjc360
I have a 1991 Dodge power ram 150 4x4 short bed truck with an A-518 non lock up transmission. I had the transmission re-built in September of 2012. Paid a lot of money for the re-build too. The transmission shop gave me a 2 year warranty on it which is expired now. When I asked about what fluid to run they said dexron3 and when I asked about a synthetic they said stay away from them the dexron3 will be just fine. So I have been running Napa house brand dexron3 in it and haven't had any issues it still shifts well when it's cold or hot. I'm going to be having some upgraded parts installed in this transmission, ether this spring with my tax return or this coming summer, I am going to have some 6 pinion steel planeterys installed up front in place of the aluminum 4 pinion planeterys and I am going to have a trans go shift kit installed. Transmission has to come out for these upgrades.m While its out I have decided I might as well run a better fluid then dexron3, it makes no sense to me to run such a dated fluid in a transmission that I will eventually have over 3 thousand dollars invested in.. I have been thinking about trying ether amsoil universal atf or mobil 1 synthetic universal or red line d4 atf or maybe even royal purple atf. I have also considered running the new dexron6 because I have heard it is a very good atf as well. People have also recommended valvoline maxlife to me. What synthetic fluid would work best forme? I live in idaho where winters are brutally cold and summers get pretty warm to, winter can get as cold as 30 below zero summer can get as hot as 100 degree. I have an external transmission cooler along with the factory tranny cooler.
Since its a USA Truck I would go Valvoline Max Life... Good Price and easy to find... Plus its FULL SYNTHETIC and its for older Transmissions and as you said yours has some miles on it. Your lucky you do not have a HONDA TRANS and have to worry about what ATF to use. Good luck.
 

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
Forgot to mention the mileage of the transmission, right now it has around 6500 miles on it. By the time I get the money for the upgrades and have them installed it might have around 8 thousand. I don't drive this truck very far or a whole lot. But during hunting season it gets a 2 week work out of being in 4x4 and climbing some huge mountains with some nasty roads. I thought the transmission shop would use the atf plus 4 fluid and was surprised when they said they put dexron3 in it and said that's what I needed to use. When I asked why not plus 4 chrysler fluid he said because it has too many friction modifiers which soften the shifts and eat up your clutches faster and tranny man also said you have a non lock up converter you don't need the friction modifiers that's in plus 4 fluid. This all came from the owner of the shop him self and he is the one who built it.
 
Last edited:

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
Transmission doesn't have high mileage, right now it has 6500 on it since being re-built in September of 2012. Can you run maxlife in a new transmission? Or will the higher mileage detergents and conditioners mess with a new tranny?
 
Joined
Mar 21, 2004
Messages
26,553
Location
Upstate NY
If you can afford and justify Amsoil ATF, that is what i would use. Most mechanics and trans rebuilders have not read a lot about oil technology nor have they done a lot of testing. If it works keep doing it.
 

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
is the mobil 1 synthetic atf a good fluid? The only thing that makes me nervouse about maxlife is the high mileage concept, this transmission does not have high mileage. Would the seal conditioners and additives for a high mileage trans work well in a new trans?
 
Joined
Oct 3, 2014
Messages
1,893
Location
NoVA
Originally Posted By: pjc360
is the mobil 1 synthetic atf a good fluid? The only thing that makes me nervouse about maxlife is the high mileage concept, this transmission does not have high mileage. Would the seal conditioners and additives for a high mileage trans work well in a new trans?
It does not have anything that would hurt seals or anything else. There is a Maxlife stop leak but that is different; Maxlife trans fluid is just a Syn universal trans fluid that I have found works very well.
 

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
Well I might consider running that,it is the easiest to find and the cheapest if it's full synthetic, I see it at my local wal-mart all the time for 16 bucks and some change for a 4 quart jug. I think I will continue to run the dexron3 untill I have the money for the parts i Want to upgrade. Have you noticed any shifting differences when switching over to maxlife atf?
 
Joined
Jul 11, 2014
Messages
2,387
Location
Paradise of Florida
Use ATF+4. Most rebuilders dont have a clue concerning fluids. Regardless of ATF cooler count, temp gauge should be added. Why didn't the rebuild already add a shift kit? rebuilder upgrades? What engine and hp? vehicle usage? If you don't want to use ATF+4, Mobil1 Amsoil RedLine RoyalPurple are easy choices.
 
Joined
Aug 5, 2002
Messages
19,238
Location
Silicon Valley
Originally Posted By: David1
Originally Posted By: pjc360
I have a 1991 Dodge power ram 150 4x4 short bed truck with an A-518 non lock up transmission. I had the transmission re-built in September of 2012. Paid a lot of money for the re-build too. The transmission shop gave me a 2 year warranty on it which is expired now. When I asked about what fluid to run they said dexron3 and when I asked about a synthetic they said stay away from them the dexron3 will be just fine. So I have been running Napa house brand dexron3 in it and haven't had any issues it still shifts well when it's cold or hot. I'm going to be having some upgraded parts installed in this transmission, ether this spring with my tax return or this coming summer, I am going to have some 6 pinion steel planeterys installed up front in place of the aluminum 4 pinion planeterys and I am going to have a trans go shift kit installed. Transmission has to come out for these upgrades.m While its out I have decided I might as well run a better fluid then dexron3, it makes no sense to me to run such a dated fluid in a transmission that I will eventually have over 3 thousand dollars invested in.. I have been thinking about trying ether amsoil universal atf or mobil 1 synthetic universal or red line d4 atf or maybe even royal purple atf. I have also considered running the new dexron6 because I have heard it is a very good atf as well. People have also recommended valvoline maxlife to me. What synthetic fluid would work best forme? I live in idaho where winters are brutally cold and summers get pretty warm to, winter can get as cold as 30 below zero summer can get as hot as 100 degree. I have an external transmission cooler along with the factory tranny cooler.
Since its a USA Truck I would go Valvoline Max Life... Good Price and easy to find... Plus its FULL SYNTHETIC and its for older Transmissions and as you said yours has some miles on it. Your lucky you do not have a HONDA TRANS and have to worry about what ATF to use. Good luck.
Honda is fine with Maxlife if Dodge is fine with it. I've been using it for 90k with no problem.
 

JC1

Joined
Nov 29, 2008
Messages
6,539
Location
Oshawa, Ontario Canada
Originally Posted By: pjc360
is the mobil 1 synthetic atf a good fluid? The only thing that makes me nervouse about maxlife is the high mileage concept, this transmission does not have high mileage. Would the seal conditioners and additives for a high mileage trans work well in a new trans?
The Mobil 1 synth ATF is very good. I used it before I switched to Max life in my 98 Toyota Sienna. I noticed no differences in performance between Mobil 1 and Valvoline Max Life. Max life is much cheaper in Canada $27 for a 5 liter jug versus $9.99 per liter. As metioned in 100s of posts on this site, try Maxlife first. Regards, JC.
 
Joined
Jan 3, 2009
Messages
14,892
Location
Illinois
I have used M1 ATF ever since they came out with it(early 90s) and have never had a trans or PS pump failure.
 

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
Originally Posted By: Greasymechtech
Use ATF+4. Most rebuilders dont have a clue concerning fluids. Regardless of ATF cooler count, temp gauge should be added. Why didn't the rebuild already add a shift kit? rebuilder upgrades? What engine and hp? vehicle usage? If you don't want to use ATF+4, Mobil1 Amsoil RedLine RoyalPurple are easy choices.
The builder didn't give me a shift kit because he said he didn't believe in using them, I asked him if I should purchase one for him to instal, he said no I will "tune" the valve body to have it shift firmer and quicker. The engine is a crate 360 magnum purchased from mopar performance in 2002 by my father it is rated at 320hp and 385 ft lbs of torque. I use this truck mainly for hunting, during hunting season October through November it will get worked hard and spend a lot of time in 4x4. I don't put to many miles on this truck and nether did my father who owned it before me. The engine has 20 thousand miles on it and is still in terrific shape. I quickly realized the shop I had re-build the transmission was more about making thier money then making the customer happy. This transmission shifts very well and I haven't had any problems with it, but he did charge me 2400 bucks and didn't even give me a shift kit. He did give me an axuilary external cooler and he routed inline with the factory cooler. When I tried asking him questions regarding fluid he would just say use dexron3. He gave me the standard re-build at a quality re-build price in my opinion. I talked to another shop in the same town and the guy told me for that price he would have given me the updated planeterys up front and a shift kit and a better warranty,who knows though he could just be saying that. I know where to get the 6 pinion steel planeterys and I already have a transgo shift kit for it so when I buy the planeterys I will bring the shift kit and some new atf to the shop I'm having put the planeterys and shift kit in. I was quoted 850 bucks to put the 6 pinion steel planeterys in and the shift kit in. So that ain't too bad. I don't really want to run atf plus 4 not that I don't believe it's not a good fluid or anything I just want to put the best atf I can in it because I don't want any problems and I know heat is the number 1 killer for a transmission and I know a quality synthetic will keep heat at bay. I don't want to have to re-build this thing again or tear into it again, I'm fine with servicing it but other then that I want this transmission to be sound when I'm done with it.
 
Last edited:

pjc360

Thread starter
Joined
Nov 1, 2011
Messages
236
Location
montana
Not that it's not sound now, I just want stronger planeterys up front and a shift kit to help keep it running cooler and shifting better.
 

JDW

Joined
Jan 8, 2014
Messages
665
Location
South
Wynn’s® Synthetic Blend ATF I and several others use this in our TBirds with no issues at all .
 
Top